Apparatus for burning carbonaceous material.



H. L. DOHERTY.

APPARATUS FOR BURNING CARBONACEOUS MATERIAL APPLICATION FILED JAN. 17. I91].

Patented Aug. 1, 1916.

2 SHEETS-SHEET 2.

FIG. 3.

Henry L. Dohertv. 8mm

HENRY L. DOHERTY, OF NEW YORK, Y.

APPARATUS FOR BURNING CARBONACEOUS MATERIKL.

Specification of Letters Patent.

Application filed January 17, 1911. Serial No. 603,086.

T all whom it may concern Be it known thatI, HENRY L. DOHERTY, a citizen of the-United States, and a resident 'of' New York city, in the county of New York and State of New York, have invented certain new and useful Improvements in Apparatus for Burning 'Carbonaceous Material,' of which the following is a specification.

This inventionrelates to traveling grates, and, in particular, to a form of said apparatus specially adapted for carryinga comparatively deep bed of fuel, so that the fuel may be burned on the grate by partial combustion to produce combustible gas. The apparatus is, however, equally well adapted for use with so-called direct-fired furnaces, in which the fuel is' subjected to complete combustion on the grate.

The object of this invention is to provide a means for burning carbonaceous material supported upon a moving grate in such a way that the quaintity of air passed through any part of the fuel bed will approximately correspond to the quantity of nnconsumed carbon in the said part of the bed.

- VVhenever a chain-grate or the like is fed with fresh fuel at one end of its inclosing chamber and discharges the resulting burned material at the opposite endof the chamber, the quantity of unconsumed fuel therein will, obviously, decrease from the feed to the discharge end where the proportion of carbon in the mass on the grate will be comparatively small, usually from G to 20%. \Vhen the air supplied for the combustion has unrestricted access to,all parts of the grate, there is a. tendency for the. greater part of the air to pass through the thinnest part of the fuel bed near the ash-discharge end of the furnace chamber. This results in a greater or less excess of free ail-passing through the fuel bed and appearing in the combustion gases, thus reducing their temperature, or else burning a corresponding quantity of the producer ga.., when the fur-" nace is being'run as a gas producer.

My invention is designed to overcome this (lefect,'by regulating the flow of air to the fuel bed approximately according to the quantity of combustible therein.

In the accompanying drawings, I have shown my invention applied to the firing of the gas producer of a gas-fired furnace. It

is evident, however, that it may be applied in connection with any direct or gas-fired furnace.

Figure 1 is a vertical longitudinal section taken through the center of the gas'producer showing the grate in longitudinal section. Fig. 2- is a part elevation detail of the chain or traveling grate and one of the sprocket wheels carrying the same, showing two of the links or grate-bars in section. Fig. 3 is a plan view of Fig. 2, but showing the left end link or bar in section, said section being taken through the uppermost row of air passages of the grate bar; Fig. 4 is a view showing the mechanism used for driving the sprocket wheel which, in turn, moves the traveling'grate at the required speed.

Briefly, my invention comprisesa gaspro, 'ducing chamber, a continuous chain-grate, working about the two sprocket wheels 7 and 7. and receiving its motion therefrom, an inclined baffle placed within the space inclosed by the traveling grate, and various other features appurtenant to the above.

The drawings show my invention applied to a furnace in which coal, 1, and clinkers,

2, are fed into a hopper, 3, which has a partition, 4, so as to keep the clinkers and coal from intermingling while in the hopper 3. The clinker and coal compartments of the hopper 3 have their respective covers, 5' and 6. As the sprocket wheel, 7, is made to slowly rotate in the directionpf the arrow by some suitable driving gear it causes the upper part of the chain grate, 8, to assume a. motion toward the .opposite end of the producer, from that where the fuel is fed,

the rate of motion being regulated-to corre-j spond with, and dependingupon, the rate of gasification ofthe fuel 1 upon thegrate 8, and being so adjusted that bythe time the fuel fed in at the front end of the producer has been burned to the desireddegree it will be discharged from the grate 8 to the grate 9 at the rear of the producer 10. On the grate 9, the mass of clinker and anyfunburned fuel discharged from grate 8, is sub-' jected totheaction of a draft-current of air toburn. out residual carborn. f v

The clinker being fed into the producer under the fuel, will form a layeraof noncombustible material upon tl1e-; grate f8 and thus protect it from excessive heat during Patented Aug. 1, 19.16.

gasificat-ion. The gas formed. in the pro ducer l0, in the'furnace shown, is led to the combustion chamber 12 through the oil take 11 which leads into the combustion chamber tangentially and (iametrically opposite the secondary air supply inlet 13, which accounts for its 'connection to the combustion chamber not being shown in Fig. 1. As the enters at the lower part of the combustion chamber '12 it is mixed with air entering through the flue 13 on the opposite side of the chamber. The-height of the combustion chamber should be such as to allow several;convolutions of the gaseous stream, thus obtaining a thorough mixture and complete combustion before lea viug the combustion chamber through the flue I l.

The combustionchamber 12 is of circular cross-section. The air and gas are entered tangentially at opposite sic. 5, thus forming a helical flame. By this device I have found. that I can secure a very complete lif'l rapid combustion of lhe producer with the minimum supply of air, thus insuring a very high flame temperature. This form of (our bustion chamber and method. of combustion 'l no not claim he: in as l ha e claimed it. in my application 7 No. 356,414, filed Feb. 3, 1907. r

14 is the combustion gas oil-take which conducts the hot gases to the place of use, for example, a steam generating chamber.

The flue and damper 39 allow the with-- drau'al of a portion of the combustion from the chamber 16, to be injected under the grate in mixture with the primary air if so desired so as to regulate the temperature of combustion in the producer.

5) is a stationary grate to receive the ashes resulting from the combustion of the fuel on the gratefl, and 40 is a. pipe leading'air from the main supply pipe 41 under the grate 5') so as, if desired to burn any fuel which may have escaped cmnluistiou while passing' through the producer 10.

4a, 4:2 and 43" are valves controlling the How of air through the respective pipes 40, 42 and 4 S.

Ap 'ilying my invention to the apparatus shown, the method of operation is as fol lows: Assuming that the producer has been brought up toproper operating condition, the fuel bed l will have a vai'y i'ig thickness r depth along its length due to the progress lug state of combustion of the fuel along.

said length; that is, the fuel bed will be thicker or deeper at the charging point where the fuel just begins to burn and the depth will dccre from this point to the oppo- Sll'lcud oi the producer, or discharge end, wacre the bed consists 'niactically of ashes and little or no combustible material and at which point the bed has its least depth From this state affairs it is evident that the amount o com ustible material upon the grate, and therefore the amount of air required for its combustion, decreases, along the grate, from the maximum. amount at the charging point to the minimum amount at the discharging point. There should thereffi'lfi be some way of coi'itrolling the distributioi of the air used in the combuietion of the Mel on the grate 8 so thatthevolume of airpassing through the grate and fuelbecl, at any point along its length, will be proporthmal to the amount of combustible material at that point. 'As stated before, this distribution of air may be obtained by using an inclined baiiie, 45, which compels a greater portion of the draft current entering under the fuel bed through the iDlBCtGl 44 to pass through the front or charging point of the PI'OtlllCBl', where the fuel bed has its greatest thickness and contaius the largest amount of unburned combustible material, and causes a gradual decrease in the volume passing through the fuel bed along the length of the grate. Therefore at the pointof least depth oi fuel bed Where there. is very little combustible material, the volume of air passing therethrough is a minimum. consequently the fuel thereon, has a slow continuous motion in the direction of the arrows, the rate of travel being such as to give ample time for the carbon of the fuel to be for the most part burned out by the tinge it reaches the discharging end, where the ashes aredi-scharged upon the secondary stationary grate 9. The main air-supply pipe ll has thre branches, one conducting the primary air through the pipe 43 to the injector The second current of air is led to the combustion chamber through the tangential inlet '13 through the pipe 42, and the third current is led through the ,small pipe 4.0 under the grate 9 through which it passes ant, burns any combustible material which has escaped complete combustion in its passage through the producer 10. The gases generated in the producer '10 are led to the combustion chamber 1'2 where they come in contact with the secondary air and are burned. as mentioned before. are led to a furnace through the line 14. A portion of the eom bus..ion gases is returned to the prodluser 10, under the grate 9. by the action of the injector 44. through the line 259. the volume thus returned being: controlledby the damper 33.

it is evident, that if the volume of air for combustion of the fuel in the producer 10 was allowed to be the same along the whole length ol the grate, that there would be a large excess of air passing through the rear end of the grate, where there little combustible material l l' l thrlx-d. when the proper volume of air was being: allowed to pass through the front end of the grate,

The grate, 8, and

The resulting combustion gases,

where the amount of combustible material in the fuel is comparatively large. On the other hand. working with a uniform flow of air along the length of the grate, if only the required amount of air were allowed to pass through the grate to burn the combus- *tible material in the rear of the grate there would result a deficiem'y in the amount of air being supplied to the front end of the producer, where the fuel bed has a larger proportion of combustible material. Again, doing away with the battle 45 and allowing a volume of air to pass through the grate to properly burn the fuel in the middle of the grate would have the evil effects that the fuel in the front of the producer would have an insufficient volume of air passing therethrough for proper combustion, and the fuel on the rear part of the grate would have an excess of air passing thercthrough. It is therefore evident that. for proper combus tion of the fuelalong the entire length of the grate, it is essential to proportion the volume of air passing ditl'erent sections thereof to the amount of comlmstible material left in the fuel at the said sections. It is also essential that the grate, upon which the traveling fuel bed is supported, be of such design that, although it will allow the air required for the proper combustion of the fuel thereon to pass theretln'ough, it will prevent the passage of the fuel, and ashes resulting from the combustion of the same. The grate, which I have shown. is of novel construction and admirably adaptcd to fill the requirements stated above to be essential to the proper operation of the invention.

92 are the linked bars comprising the grate 8. These bars, when assembled to form the grate 8, prevent the fuel or ashes from falling through it to the chamber 46 and, at the same time, permit free passage of the air required for combustion of the fuel. This is preferably accomplished by having bars as shown in Fig. 2, which oic tain numerous slots. 9 the slots being preferably inclined as shown, so that the air may pass through. while the fuel cannot work itself up through the inclined slots.

The bars have a shorter side liXed at. approximately. right angles to the conveycr chain and a longer side inclined thereto. The bars are. preferably, set with their inclined side in advance of the shorter side. As the bars are preferably slotted on the :nhance side only. in order that ashes will not work through the bars while the same are passing over the sprockets or drums at the discharge end (as they would were the bars slotted on the rearward side) it is advantageolr bare the inclined side in advance in c er to take advantage of the greater slot area thereby made available. The advantage in having the one side substantially perpendicular to the upper flight of the conveyer chain is that the span of the bars is thereby made shorter, thereby permitting the inclusion of a greater number of bars in the train. The inclination of the other side of the bars may be fixed according to the preference of the designer, within certain limits, the aim being to have the inclined side long enough to permit of sufficient slot area for the proper supply of air, while, at the same time, not unduly i11- creasing the span of the bar.

The driving shaft 7 has two sprocket wheels, 7, keyed to it, only one of which is shown in Figs. 2 and 4. Pins, 94, connect, in the arrangement shown, the rear lower side of one grate-bar with the front lower,

side of the adjacent grate-bar, and they project beyond both ends of the links 92 and through the two heavy links 95 and 95, whichlatter links when assembled form the sprocket chain which is directly driven by the wheels 7 and thus imparts motion to the grate as a whole. The links 95 with their corresponding links 95 are spaced apart so that the teeth fit of the wheel 7 may pass between them and engage the cross pins 97, by which means the grate is carried around by the wheel 7 in the direction of the arrow.

The bars 92 project into the recess 98 in the side walls 46 and 46, 46' only being shown, leaving as small a clearance as practicable between them and the walls 46 and 46' on the upper side of the grate. At the ends of each bar 92, the projecting lugs 99, extend over the joints of the links and prevent whatever material may work itself through the clearance from getting in the joints. 1 j

The driving shaft extends through the side \all through a heavy bearing 7 and is driven by any suitable reducing gearing. As the forward speed of the fuel onthe grate S lllll l be very slow in order to allow a sutlicient length of time for the. gasilication of the fuel during its passage through the length of the gas producer 10, the reduced speed ratio of the engine shaft and the shaft 7" must be large. In the drawings, Fig. -l shows one method for obtaining such speed reduction. in which 100 is a worm on the main driving shaft, 100', driving the large worm gear 101. The worm gear 101 is keyed to the shaft 102. on which is another worin, 1025, which, in turn, drives the second worm wheel, 104, which is keyed to the driving shaft 7". driving the wheels 7 as already explained. By increasing the number of teeth on the worm wheels, or by increasing the nmnber of wheels and worms, any reduction of speed desired may be ob tained.

105 and 106 are supports for the shafts 102 and 7", respectively.

107 indicates a means for guiding the up per part of the grate 8 hetween the sprocket wheels. the projertii'i; pieces an which pre vent material from getting into the joints of the links slide upon these Z-pieees whieh are supported in the walls of 10. and the part of the grate supporting the fuel is prevented from sagging.

Having described my invention, what I claim is: i

1. A t'aveling grate eomprising a plurality ot' Q'ratwbars having;' an inverted trough-shape on. the upper run of the grate, the! said grate-bars each having one side ionizer than the otherand having a plurality of apertures in the said longer side for the passage of air therethrough, and means tor joining the short side of awh gratwhar to the Ion; side of an adjarent bar to form an endless train, the junetures between said grate-bars being substantially ash-tight.

2. A traveling grate comprising a plurality of grate-liars of substantially uniform eross-seetion and having an inverted troughshape on the upper run of the grate, the said liars eaeh having), one side longer than the other and having a plurality of apen tures in the said longer side for the passage of air therethrough. aid apertures being inolined downward from the interior of said gratebars and means for joining the short side of eat-h grattehar to the long side of an adjaeent grate bar to form an endless train.

3. i\ taveling grate comprising a pin-- rality of grate-bars of substantially uniform irossseetion and of inverted trough shape on the upper arm of the grate. the said gratebars (Zit'll having; one side longer han the other, the length of the said longer side being approximately equal to the length of the said shorter side divided by the eosine ot' the angle included between the said sides. the said longer side having: a plurality of apertures therein.

4. A traveling grate comprising a plurality ol' grate-bars of substantially uniform cross-section and having: an inverted troughshape on the upper run of the grate. the said grate-bars ea -h having one side longer than the other, the length of the said longer side being approximately equal to the length of the said shorter side divided lay the eosine ot' the angle ineluded betneeu the sail sides and having: a plurality of apertures and means for joining the hort side of each grate'har to the iongr side of an adjarent. grate bar to form an endless train.

5. A traveling: grate (.(Hllllllrllllg a plurality of gratediars having an inverted trough-shape when on the upper run ol the grate. the said grate bars eaeh having one side longer than the other. the length il the said longer side llt'lllg approximately qual to the length of the said horter side ll 'itlt'd by the z-osiue ol' the angh inrluded lie-tween the said sides and luv mg a plurality t in (lined apertures for the passage of air theretln'ough. said apertures leading from the interiow'ot said z rate-hars in a diipetion "n x of said angle and nfi-anslor joining the short side of each grate-liar to the lOllQ side f an ad i.-,1 :e!1t grate-liar to Form an enohrss train.

(3. A tzavehng grate comprising: a plu rality ot' grate-liars having: an inverte-l troughhape on the upper flight of ;.:rat the s id gratears earh having: one. side longer than the ()Eln rt the l lifllii of the said longer si Le being: approximately ed to the length of the said horter side vi'ded hy the e-tn-ine of the angle ineluded iwlween llilfiaiiitl sidessthe l nger side hhvir a i 'u'alitv of iin iihed apertures for the pa sasre of "ir ti\i lt-lllliiil "ii. said apertures leading! train the interior of said grate-l ar in a dn'eetion away f om the ertex oi riitl angle. means for joining said grateha a siih to side to form an endless train. 1% train liavinei in!) upper and a lower flight. and a halite located between said l'lijl'l'its and adapted to retard the low l a r toward the rear end of the said upper tligrht of said grate.

T. A tzavriing hate emnprising a Plll' ralitv oi grate-hers; of inverted \l shaped rross set-thin when on the upper run of the grate one. 1 grate-bars having apertures therein for the passof air therethrough, Said. gratediars being directly joined side to side to form an endless train.

5 L traveling rate roinprh-aing a phi ralitv of gratehars oi inverted Vshaped rrol :sert ion when on the upper run of the grat one side of each of r id grate-bars having, apertures therein for the passage of air therethrougi'h. said apertures being so disposed as to prevent material upon said grate tron: passing therethrmigrh said gratehars lining directly joined side to side to I form an endless train.

9. A traveling grate comprising a plurality oi grailediars of inverted troughshaped -ross-srrtion when on the upper run of the grate. said iratediars ha ing :2 pin-- rality oi apertures. lor the pasbage, of air therethroueh. said apertures living -41 dis posed as to prevent material upon ma g1? ate lroin paasing then-through rsaid gratebars hein; dirertiy ioified side to aide to Form an -ndless train in snrh in; t r as to form substantially a h-tight junrtuies between the bars.

h). A taveline grate romprising a pln-- rality ot' giltlttdrllfi of inverted trouizln shapedwrossseetion when on the upper run of the grate. said trouglrshaped grate-bars having a plurality of apertures in the sides for the passage of air therethrmigh. said apertures being int-lined downward from the interi rs oi said gratr'bars. and means for dirertly joining said ti'ouglr-slniped grate-bars side to side to form an endless train, the junctures between said grate-bars being substantially ash-tight;

11. A traveling grate comprising a plurality of grate-bars having an inverted trough-shape when on the upper run of the grate, the said'grate-bars each having one side longer than the other and haying a plurality of apertures in the advance side for the passage of air therethrough, and means for joining said grate-bars side to side toform an endless train, the junctures between said tight.

12. A traveling grate comprising in combination a plurality of trough-shaped gratebars, said graterbars being in inverted position onthe upper run of the, grate and having one side set substantially perpendicular to the horizontal when in. functional position, said grate-bars having a plurality of apertures, said apertures being arranged to permit free passage of air and to prevent the gravity flow of solid material therethrough, joining means for joining said grate-bars side to side to form an endless train, and means for transmitting motion to said endless train, said means comprising sprocket chains attached to and cooperating cooperating with said sprocket chains.

13. A traveling grate comprising in combination, a plurality of trough-shaped gratebars, said grate-bars being set inverted and with one side substantially perpendicular to the horizontal and the other side inclined when in functional position on the upper run of the grate, the sides of said trough-shaped grate-bars having a plurality the interval between the extremities of the two sides bf each grate-bar, the links of adjacent bars being pivotally connected to form an endless sprocket chain, a laterallyprojecting lug attached to each end of each of said grate-bars and extending over the pivotal connection of the sprocket link of that grate-bar with the sprocket link of an adjacent grate-bar, sprocket wheels cooperating with said sprocket .chain, and mean for rotating said sprocket wheels.

14. A traveling grate comprising in combination, a plurality of trough-shaped gratebars, the said grate-bars being set inverted on the upper run of the grate and of substantially uniform cross-section and having grate-bars being substantially ash-- with said endless train, and sprocket wheels one side longer than the other, said gratebars having a plurality of apertures in their sides, said apertures being inclined outwardly and away from the vertices of said trough-shaped grate-bars, whereby free passage is provided for air but the gravity-flow of solid material through said grate-bars is prevented when said grate-bars are in functional position, means for flexibly joining the shorter side of each grate-bar to the longer side of an adjacent grate-bar to join said grate-bars side to side to form an endless train, means for imparting motion to said endless train, said means comprising sprocket links spanning the space between the two sides of'each of said grate-bars, the links of. adjacent bars being pivotally connected to form an endless sprocket chain, a laterally projecting lug attached to each end of each of said gratebars and extending over the pivotal connection of the sprocket link of that grate-bar with the sprocket link of an adjacent grate-bar, sprocket wheels cooperating with said sprocket chains, and means for rotating said sprocket wheels to impart motion to said chains and the attached grate-bars.

15. A traveling grate comprising in combination a plurality, of trough-shaped gratebars, said grate-bars being laid transversely to the direction of travel of said grate and inverted on the upper run of the grate and having one side shorter than the other, the longer side of each of said grate-bars having a plurality of apertures therein, said apertures being inclined outwardly and away from the vertex of said trough-shaped gratebar, whereby passage is provided for air but the gravity-flow of solid material through said apertures is prevented when said bars are in functional position, means for pivotally joining the shorter side of each gratebar to the longer side of an adjacent gratebar to join the said grate-bars side to side to form an endless train, means for imparting motion to said endless train, said means comprising sprocket links spanning the space between the sides of each of said grate-bars, the links of adjacent grate-bars being pivotally connected to form an endless sprocket chain, a laterally projecting lug attached to each end ofeach of said grate-bars and extending over the pivotal connection of the sprocket link of that gratebar, with the sprocket link of an adjacent grate-bx"; a pair of sprocket wheels suitably mounted on a shaft to cooperate with said sprocket chains at each end of said grate, and a double worm gear for imparting rotation to one of Said shafts, whereby motion is imparted to said traveling train.

16. A traveling grate comprising in combination, a plurality of trough-shaped grate bars of substantially uniform cross-section, the said grate-bars being set inverted on the 30 upper run of the grate and baring one sir 1c longer than the other. said grate bars haw ing a pluralitv of apertures in one side, said apertures being so positioned as to permit the )assage of air while prrventinp; the gravitv-flow ofsolid material therethrough, means tor joining; said gram-liars side to side in pivotal connection to term an endless train. and an inclii. d ballle for regulatin; the distribution of air along the length said grate.

17. A traveling grate comprising in comlwination, a plurality of trough-shaped gratebars each of said gratwbars having a reia tivcly short side and a rclativel long side and being set inverted on the upper light of the grate, the length of the said relatively long, side being approximately equal to the length of the wlativei short sii divided by the cosine the angle included between the sides, one side oi earl; of said gratcdwars having a plurality of apertures, means for joining said grate-bars side to side in pivotal connection to form an endless trainand an inclined ballle for diminishing the flow of air along said grate in the direction of travel of the upper flight of said grate 18. A tra elinp grate comprising in combination, a plurality of trough-shaped gratebars, each of said grate-bars having a relatively short side and a relatively long side, and being set inverted on the upper flight of the grate, the length of the said relatively long side being approximately equal to the length of the relatively short side divided by the cosine of the angle included between the sides, the longer side of each of said grate-bars having a plurality of apertures, said apertures being inclined outwardly and away from the vertex of said grate-bar, means for joining said gratobars side to side in pivotal connection to form an endless train, and an inclined battle interposed between the flights of said endless train to diminish the flow of air toward the discharge end of said grate.

19. A traveling grate comprising in combination, a plurality of trough-shaped gratobars, the said grate-bars having a relatively short side and a relatively long side and being set inverted on the upper flight of the grate; one side of each of said grate-bars having a plurality of apertures tl'icrcin, said apertures being inclined outwardly and away from the vertex of said trough-shaped grate-lair, means for joining the short side of each grate-bar to thc long side of an adjacent grate-bar to 'l'orin an endless train, said train having an upper real-hardly moving flight-j and a lower outwardly moving flight, an inclined ballie interposed between the flights of said grate said ballle having its rear portion in close juxtaposition to the lower face of the upper flight'of said endless train and extending forward and down ward therefrom, whereby the flow of air along said grate is diminished in a direction toward the rear of said grate.

20. A traveling grate comprising in combination, a plurality of trough-shaped gratebars, each of said grate-bars having a relatively short side and a relatively long side and. being set inverted when on the upper flight of said grate, the length of the said relatively long side being approximately equal to the length of the, said relatively short side divided the cosine of the angle included bct'vvecnthe sides, one side of each of said grate bars having a, plurality of apertures, said apertures being ii'iclined outwardly and away from the vertex of said troughshaped gratcbar, means for joining the said relatively short side of each gratin bar to the said relatively long side of an ad jueent bar to form an endless train, said train having an upper rearwardly moving flight and a lower outwarlilly moving flight, an inclined battle interposed between the flights of said grate, said baffle having its rear portion in close juxtaposition to the rear portion of the lower face of the said. upper flight of said grate and extending forward and downward toward the front end of said grate, whereby the flow of air along said grate is diminished in a direction toward the rear of said grate.

21. A traveling grate comprising in combination, a plurality of trough-shaped gratebars, the said grate-bars being set inverted when on the upper flight of the grate and hr. ring their sides rigidly joined, a plurality of lugs projecting from each of the sides of each of said grate-bars, said lugs being so spaced on the respective sides of the respective grate-bars that the lugs onadjacent sides of adjacent grate-bars will intermesh with each other when said grate-bars are assembled in functional combination, and mezins for joining said grate-bars side to side to form an endless train.

22. A travelin grate comprising in combination, a plurality of "rate-bars, said grate-bars having an inverted trough-shape when on the upper run of the grate. and having their sides rigidly joined, a plurality, of lugs projecting from each side of each of said grate-bars, said lugs being so spaced or the respective sides of the respective gratebars that the lugs on adjacent sides of adja cent gratc-bars will intermesh with each other when said grate-bars are assembled in functional combination, longitudinal perforations in said lugs, the sail l erforations in the said lugs of each sideof said grate bars being arranged in alincment, the alinement of said perforations o the said lugs of adjacent sides of adjacent gratcbars being so positioned that the two sets of perforations will be in alincment with each other When-tho said grate-bars are assembled in functional combination, and a plurality of hcaz-ing pins, one of said pins being inserted through the, alincd perforations of the lugs of adjacent sides of adjacent gratshars when said grate -bars are assembled, whereby the said grate-bars are joined side to side to form an eidlcss train.

A. traveling grate omprising in comliination, a plurality of gore-bars having an inverted troaglrshape when in the upper end. of the grate, a lnra!ity of lugs projecting from cach '5 each of said gratohars, said hein j so spaced on the respective sides of the respective grate-bars that the la s on adicc'nt sides oasis will in sa d gratc-hars are assemhlyd in functional coniliinatiom said ll: s being provided with longitudinal perforations and said perforations in the id lugs of each side said ,qraichars lici arranged in alincment, the zilincment ills said perforations of the men of adjacent grateany; so positioned that the two of :nmtions will no in alinement with each. tha when the said gratsloars are a; nlcai in functional combination, a plurality iearing pins, one of said pins being inthrough the alincd perforations of the i iant sides of adjacent grate-liars grate-hairs are assenihled to join Y '5 side to side tofi'form an en ld a plurality of sprocket links between the sides of said :q'arocke't links being joined and pivoted on said hearing:

i, in ii ling grate comprising in com :irslity of trough-shaped grate Icd when :n the upper flight of a plurality of lugs projecting p as being so spaced on the: respective of thc respective gratwhars that the a adjacent sides of adjacent gratewiii inter-mesh with each other when i, 7 bars are assembled. in functional coznlim :lfliL said lugs being provided With lo'ngitirliiml perforations and said perforations in the said lugs of each side of said gratwbsrs being arranged inv alincment, the alincment of the said perforations of the said lugs of adjacent sides of said gratshn rs being so positioned that the two of per-- {orations will be in alinemcnt with each other when the said grate-bars are asscnr bled in functional combination, a plurality of hearing pins, one of said. pins being inserted through the alineclperforations at of adjacent gratc- Y mesh with each other when side of each of said gratshars,

sprocket; links spanning the space between the sides of said grate-bars, said sprocket links being joinciil together by and pivoted on said hearing pins, and an inclined baflle interposed between the fligliits of said endless train, said halile having its rear position in close juxtaposition to the; lower face of the said upper flight. and extending forward and downward therefrom.

25. A traveling grate comprising in combination, aplurality of trough-shaped gratebars set inverted when on the upper flight of the grate, a plurality of lugs projecting from each side of each of said grate-bars, said lugs being so spaced on the respective sides of the respective grate-bars that the lugs on the adjacent sides of adjacent grate-bars will in terms-sh with each other when said gratehars are assci'nliilcd in functional combina: tion, said lags being provided with longitudinal perforations and said perforations in the said lugs of each side of said grate-bars l'icing in alincinent, the alinement of the said pcrfo nt'ions of the said lugs of adjaccnt sides of said grate-bars being so positioned that the two oi. perforations will hs in aiincmcnt with each other when the said iioltiars are assembled in functional combination, a plurality of bearing pins, one of saidv pins being inserted through the alincil perforations of the, lugs of adjacent sides adiaccnt gratshsrs are assembled to join said grate bars .v is to side to form as. endless train said train having an upper flight and a lower gratohars when said flight, a tilurality o't sprocket links span- 10G Ring the distancc between the sides of said gratc br-irs, said; sprocketlinks being joined together by and pivoted on said hearing pins, a pair of sprocket wheels suitably mounted on a shaft to coiiperato with said sprocket chains at each and of said grate, moans for imparting rotation to one of said shafts, and an inch: -d bathe interposed between the flights of said endless train, said baffle having its rear portion in close juxtaposition to the in er face of said upper flight and extending forward and downward therefrom. Signed at New York city, in the county of New York and State of New York, this 16th day of January, A. l). 19.11.

HEN BY L. DOHERTY. Witnesses:

.3. i l. IVZ'GMILLIN, F. L. BLACKBURN. 

